This application relates to a pressure regulating valve which may be utilized in a fuel line for an aircraft engine.
A gas turbine engine is typically used to power an aircraft. A fuel system provides fuel to various portions of the gas turbine engine. Fuel is primarily delivered into a combustor section of the gas turbine engine. Airflow through the gas turbine engine is compressed by one or more compressors, mixed and burned with fuel in the combustor, and then expanded over one or more turbines. The fuel is supplied to the gas turbine engine by a fuel pump from a fuel supply, and passes through a filter on the way to the engine. The fuel system also includes various valves, such as a pressure regulating valve, high pressure relief valve, filter bypass valve, etc., which cooperate with each other to supply fuel to the gas turbine engine in a controlled and accurate manner.
The metering valve supplies a specified amount of fuel to the engine for various operating conditions. The pressure regulating valve sets a predetermined pressure differential across the metering valve. This allows control over flow to the engine based on metering valve position. Under certain conditions, not all of the fuel being supplied by the pump is needed by the engine. The pressure regulating valve also returns excess fuel back to the fuel pump. Existing pressure regulating valves may sometimes result in undesirable pressure setting shifts at different operating conditions.